A method and an apparatus for concentrating liquid-drenched material by rolling a string of that material while the string is embraced by an endless straining cloth belt are known, for instance, from U.S. Pat. No. 4,017,398. Apparatus of this type which are known are encumbered with certain drawbacks. For instance, a single straining cloth belt which embraces a material string has the tendency to rupture at the edge regions of the string when rolling at high pressure, and generally has a width which is more than twice the breadth of the rolled material string, resulting in large space requirements.
An object of the present invention is to provide a novel method and novel apparatus with which the aforesaid drawbacks are avoided at least to a substantial extent.